Jamie Maclaren savoured the proudest moment of his career after hitting a hat-trick in Australia's straightforward 5-0 win over Nepal in World Cup qualifying.

The Melbourne City striker translated his club form to the international stage as he struck twice in the opening 19 minutes in Canberra to set the Socceroos on course for a second successive victory on the road to Qatar 2022.

Maclaren, 26, completed the scoring with a well-taken third in the 90th minute, improving his record for Australia to four goals in 14 appearances following a lean start in the green and gold.

Critics had questioned his ability to build on a fine A-League record but Thursday's treble in the nation's capital, albeit against limited opposition, vindicated his inner confidence.

"My proudest moment in a football jersey," Maclaren told Fox Sports after the match.

"Representing my country in Canberra, scoring a hat-trick, as a striker it's the best feeling.

"I owe a lot to my team-mates and the manager for putting faith in me. At times you question whether you're good enough at this level and I feel I am. I believed through those tough years."

Though he claimed the match ball, Maclaren was forced to share the limelight at GIO Stadium with a fellow former Scotland youth international.

Aberdeen-born Harry Souttar changed his allegiance to his mother's homeland earlier this year and enjoyed a debut to remember, scoring a headed double either side of half-time.

The towering centre-back, who is on loan at Fleetwood Town from Stoke City, only stepped foot in Australia for the first time this week but has impressed head coach Graham Arnold.

"He's just such a great kid," Arnold said of Souttar, the brother of Hearts defender and full Scotland international John Souttar.

"Let's see him against a bigger team and a better team defensive-wise because when I see him at Fleetwood Town he's doing exceptionally well.

"There's a little bit of competition there with him. He's so calm on the ball and he's so relaxed. He's a great find for us."

Australia's next Group B game in the second phase of the Asian Football Confederation qualifying route is against Chinese Taipei in Kaohsiung on Tuesday.